System and method for overspeed detection and protection in engine

Abstract

An engine includes a gearbox coupled to a first element and a second element. The engine may include a first speed sensor positioned on an input side of the gearbox, the first speed sensor operable to detect a first speed of the first element. The engine may also include a second speed sensor positioned on the output side of the gearbox, the second speed sensor operable to detect a second speed of the second element. The engine includes a controller including a processor and a memory coupled to the processor. The processor may be configured to receive data from the first speed sensor and the second speed sensor. The processor is further configured to detect a trigger event based on data from the first speed sensor and data from the second speed sensor. Upon detection of the trigger event, the processor transmits a command to the engine operating system.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 541,010, filed on September 28, 2023, which is incorporated herein by reference in its entirety. Technical Field

[0003] These teachings generally relate to overspeed detection and protection in engines, such as gas turbine engines. Background Art

[0004] General engines and aircraft engines may have a gearbox that regulates the speed between different elements in the engine. Failure of the gearbox or elements coupled thereto may result in an overspeed condition, which, if not controlled, may damage the engine or its components. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Various needs are met, at least in part, by providing a method of detecting and controlling overspeed in an engine as described in the following detailed description, particularly when studied in conjunction with the accompanying drawings. A complete and enabling disclosure of the various aspects of the present specification, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification with reference to the accompanying drawings, wherein:

[0006] Figure 1 is a block diagram of a system for detecting overspeed of an engine shaft according to various embodiments of these teachings;

[0007] Figure 2 is a flow chart of a method for detecting an overspeed condition of an engine according to various embodiments of these teachings;

[0008] Figure 3 is a flow chart showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0009] Figure 4 is a diagram showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0010] Figure 5 is a diagram showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0011] Figure 6 is a flow chart showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0012] Figure 7 is a flow chart showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0013] Figure 8 is a diagram showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0014] Fig. 9 is a diagram showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0015] Fig.10 is a flow chart showing a method for detecting overspeeding according to an embodiment of the present disclosure;

[0016] Fig.11 is a schematic cross-sectional view of a turbine engine taken along an axis of the turbine engine according to an embodiment of the present disclosure;

[0017] Fig.12 yes Fig.11 A schematic cross-sectional view of a turbine engine of FIG. 1 showing an alternative speed sensor placement; and

[0018] Fig.13 yes Fig.11 A schematic cross-sectional view of a turbine engine, showing alternative speed sensor placement.

[0019] The elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size and / or relative position of some elements in the drawings may be exaggerated relative to other elements to help improve the understanding of the various embodiments of the present teaching. In addition, common but well-understood elements that are useful or necessary in commercially feasible embodiments are generally not depicted to facilitate less obstructed observation of these different embodiments of the present teaching. Certain actions and / or steps may be described or depicted in a specific order of occurrence, but those skilled in the art will understand that such specificity about the sequence is not actually required. DETAILED DESCRIPTION

[0020] The method provided herein uses the speed sensor positioned at the input side and the output side of the gearbox to detect the overspeed of the engine shaft, and limits or stops the fuel supply to the engine, or controls other operating aspects of the engine to prevent overspeed events.When the rotating speed of the engine exceeds its design speed limit, the engine is in an overspeed state, and beyond this design speed limit, the operation of the engine may become unsafe.The method described herein can be applied to all types of aircraft engines, including jet aircraft engines, rotorcraft (e.g., helicopter) engines or any other type of aircraft engines of all types and structures.In some respects, the method provided herein is applied to commercial turbofan engines, and attempts to prevent or otherwise respond to the overspeed state in the engine by controlling the combination of fuel flow, blade pitch or these systems or any other aircraft systems.

[0021] Aircraft and other engines usually have a gearbox. In the event of a failure in the gearbox or a shaft connected thereto, the engine may include overspeed monitoring and protection. Traditional overspeed monitoring and protection may involve monitoring the speed of a shaft, and may determine or detect overspeed when a shaft reaches a specific speed. This traditional method may cause the disc to be oversized to avoid bursting, which increases engine weight and fuel consumption. The method described herein detects an impending overspeed state (e.g., a rotational speed close to a design limit) by monitoring a first speed of a first element connected to the input side of the gearbox and a second speed of a second element connected to the output side of the gearbox. The difference between the first speed and the second speed may serve as a trigger event, causing the controller to stop or slow down the engine or otherwise respond to the trigger event. The trigger event may be any difference in a known relationship between the first speed and the second speed, and may indicate an overspeed state. In this way, it is not necessary to sense the actual overspeed state, but to detect the difference between the first speed and the second speed. Advantageously, the method described herein may detect and respond to an overspeed state faster than conventional methods.

[0022] The above and other benefits may become more apparent upon a thorough review and study of the following detailed description.

[0023] In addition to the different specific meanings that have been set forth herein, the terms and expressions used herein have the ordinary technical meanings given to these terms and expressions by those skilled in the art in the above-mentioned technical field. Unless otherwise specifically indicated, the word "or" used in this article should be interpreted as having a disjunctive structure, not a conjunction structure. Unless otherwise specified herein, the terms "connect", "fix", "attach to", etc. refer to both direct connection, fixation or attachment, and indirect connection, fixation or attachment through one or more intermediate components or features.

[0024] The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0025] Approximate language, as used herein throughout the specification and claims, is applied to modify any quantitative representation that may be permissibly varied without resulting in a change in the basic function to which it is related. Thus, values ​​modified by terms such as "about," "approximately," and "substantially" are not limited to the precise values ​​specified. In at least some cases, approximate language may correspond to the precision of an instrument used to measure a value, or the precision of a method or machine used to construct or manufacture a component and / or system. For example, approximate language may refer to within a 10% margin.

[0026] Reference now Figure 1, describes an example of a system 100 for sensing and reacting to overspeed in an engine. The system 100 includes an engine 102. The engine 102 includes a gearbox 104 coupled to a first element 106 and a second element 108. The gearbox 104 has an input side including an input shaft and an output side including an output shaft. The first element 106 is disposed at the input side of the gearbox 104 and is coupled to a power source. The first element 106 may be, for example, an input shaft of the gearbox 104 or a component coupled thereto. The second element 108 is disposed at the output side of the gearbox 104 and receives rotational energy from the input shaft of the gearbox. The second element 108 may be, for example, an output shaft of the gearbox 104 or a component coupled thereto. The gearbox 104 regulates the speed between the first element 106 and the second element 108. A first speed sensor 110 is disposed at the input side of the gearbox 104. A second speed sensor 112 is disposed at the output side of the gearbox 104.

[0027] The engine 102 can be any type of aircraft engine, such as a ducted or non-ducted aircraft engine. In some aspects, the engine 102 can be a gas turbine engine for an aircraft. The gearbox 104 can be any type of gearbox. In some aspects, the gearbox 104 is a power gearbox of a gas turbine engine. In some aspects, the engine 102 is a turboshaft engine for a rotorcraft (such as a helicopter), and the gearbox 104 is the main gearbox of the rotorcraft. The gearbox 104 can be mounted to any aircraft component in any suitable manner or using any suitable structure. For example, the gearbox 104 can be mounted around the shaft of the engine 102. It should be understood that any gearbox mounting structure or method described herein is an example, and other examples are possible.

[0028] The first element 106 and the second element 108 can be any type of engine parts, components, structures, machines or other elements. In one example, the first element 106 is a high-speed shaft of a gas turbine engine. In another example, the first element 106 is a component of a high-pressure shaft of a gas turbine engine, such as a high-pressure turbine. In one example, the second element 108 is a low-speed shaft of a gas turbine engine. In another example, the second element 108 is a component of a low-pressure shaft of a gas turbine engine. Each element can then have a sub-element or sub-component. The high-pressure turbine can be coupled to the gearbox 104 by a rotating shaft (e.g., an input shaft of the gearbox 104). The gearbox 104 is coupled to the fan blades by various mechanical arrangements (such as shafts (e.g., output shafts of the gearbox 104) and gears). It should be understood that although most of the content disclosed herein is described with respect to coupling the gearbox 104 between the fan blades and the high-pressure turbine, the gearbox 104 can also be coupled to other aircraft elements.

[0029] The first speed sensor 110 and the second speed sensor 112 are operable to measure speed. The first speed sensor 110 and the second speed sensor 112 may be any type of sensor for measuring speed. In some examples, one or more of the first speed sensor 110 and the second speed sensor 112 may be a variable reluctance sensor (e.g., a gear-based sensor), a surface acoustic wave (SAW) sensor, a blade beta angle sensor, a speed sensor that measures the speed of the motor, or a torque sensor that measures the torque of the motor.

[0030] The first speed sensor 110 is positioned on the input side of the gearbox 104. The first speed sensor 110 measures the speed of the first element 106. In some approaches, the first speed sensor 110 is mounted on or near the second element 108 or a component coupled thereto. In one example, the first speed sensor 110 can be mounted to a frame or some other non-moving or non-rotating component of the engine 102. The mounting location of the first speed sensor 110 can depend on the type of sensor employed. For example, a SAW sensor can include an element disposed on the input shaft of the gearbox 104, with an antenna mounted to a nearby frame or bearing support. As another example, a variable reluctance sensor can be inserted through an opening in the frame so that the sensor tip is located near a toothed wheel coupled to the input shaft of the gearbox 104.

[0031] In one example, the first speed sensor 110 is a gear-based variable reluctance sensor and is mounted on the input shaft of the gearbox 104. Such a variable reluctance sensor may be composed of two or more gears (e.g., an input gear coupled to the input shaft of the gearbox 104 and an output gear coupled to a sensor mechanism of the variable reluctance sensor). The input gear rotates at the same speed as the input shaft and also rotates the output gear. The sensor mechanism of the variable reluctance sensor detects the movement of the output gear and generates an electrical signal proportional to the speed of the input shaft. The sensor mechanism of the variable reluctance sensor may be, for example, a magnetic sensor mechanism or an optical sensor mechanism.

[0032] The second speed sensor 112 is positioned on the output side of the gearbox 104. The second speed sensor 112 measures the speed of the second element 108. In some approaches, the second speed sensor 112 is mounted on or near the second element 108 or a component coupled thereto. In one example, the second speed sensor 112 can be mounted to a frame or some other non-moving or non-rotating component of the engine 102.

[0033] In one example, the second speed sensor 112 is a gear-based variable reluctance sensor and is mounted on the output shaft of the gearbox 104. Such a variable reluctance sensor may be composed of two or more gears (e.g., an input gear coupled to the output shaft of the gearbox 104 and an output gear coupled to a sensor mechanism of the variable reluctance sensor). The input gear rotates at the same speed as the output shaft and also rotates the output gear. The sensor mechanism of the variable reluctance sensor detects the movement of the output gear and generates an electrical signal proportional to the speed of the output shaft of the gearbox 104.

[0034] In some embodiments, the first speed sensor 111 may be Figure 11-13 , and the second speed sensor 112 may be one of the sensors 1180, 1180' or 1180" shown in FIG. Figure 11-13 One of 1182 or 1182' shown in and described below.

[0035] The controller 114 may be any type of electronic device that executes electronic computer instructions, such as a processor, microcontroller, etc. The controller 114 may have a memory coupled to the processor that stores programming instructions for executing the various algorithms and functions described herein.

[0036] The controller 114 may be configured to receive and process electrical signals generated by the first speed sensor 110 and the second speed sensor 112. In some approaches, the controller 114 may be configured to analyze the electrical signals from the first speed sensor 110 and the second speed sensor 112 to detect a triggering event. The triggering event may be any event indicating an overspeed condition of the engine 102. In one example, the triggering event may be a deviation between a known or expected relationship between the speed of the first element 106 (e.g., detected by the first speed sensor 110) and the speed of the second element 108 (e.g., detected by the second speed sensor 112). In another example, the triggering event is when the difference between the speed of the first element 106 and the speed of the second element 108 exceeds a threshold. In yet another example, the triggering event is when the rate of change between the speed of the first element 106 and the speed of the second element 108 exceeds a threshold.

[0037] In some approaches, the controller 114 may be configured to transmit or communicate commands to control the operation of the engine 102. For example, the controller 114 may communicate commands to one or more engine operating systems 116.

[0038] Engine operating system 116 may be any system that controls engine 102, or in some examples, an aircraft powered by engine 102. For example, one or more engine operating system 116 may include a system that controls fuel flow to engine 102, changes the pitch of fan blades of engine 102, vents compressor exhaust gas overboard so as not to provide flow to a turbine, etc. One or more engine operating system 116 may include devices (such as shafts, gears, valves, arms, motors, or other components) controlled by a control system, which may be operated by controller 114, for example, by receiving commands from controller 114.

[0039] In operation, as described elsewhere herein, the first speed sensor 110 measures the speed of the first element 106 (e.g., the first speed), and the second speed sensor 112 measures the speed of the second element 108 (e.g., the second speed). The controller 114 analyzes the measured speeds of the first element 106 and the second element 108 to detect or predict an overspeed condition of the engine 102. The controller 114 can transmit commands to one or more engine operating systems 116 to respond to or prevent an overspeed condition of the engine 102 based on the measured speeds, and in some examples, based on a relationship between the measured speeds.

[0040] Reference now Figure 2 , provides an example of a method for monitoring and controlling overspeed in an engine. The engine may be reference Figure 1 The engine 102 is shown and described. In some examples, the engine is referenced Fig.11 Turbine engine 1110 is shown and described. However, it is contemplated that the methods may be employed in any number of suitable engine configurations.

[0041] At block 202, a first speed sensor senses a first speed of a first element of an engine. The first speed sensor is positioned on an input side of a gearbox of the engine. In some examples, the first element is a reference Figure 1 The first element 106 is depicted, and the first speed sensor is a first speed sensor 110 .

[0042] At block 204, a second speed sensor senses a second speed of a second element of the engine. The second speed sensor is positioned on an output side of a gearbox of the engine. In some examples, the second element is a reference Figure 1 The second element 108 is depicted, and the second speed sensor is a second speed sensor 112 .

[0043] At block 206, the controller detects a triggering event based on the first speed and the second speed. The triggering event may be, for example, any deviation between a known or expected relationship between the first speed and the second speed. In one example, the triggering event is when the difference between the first speed and the second speed exceeds a threshold. In another example, the triggering event is when the rate of change between the first speed and the second speed exceeds a threshold. The controller may detect the triggering event using one or more of the methods described herein. Figure 3-10 Various methods of detecting a triggering event are described. In some examples, the controller may be a reference Figure 1 Controller 114 is described.

[0044] At box 208, the controller takes action when a triggering event is detected. The controller may take action by transmitting a command to trigger an action in one or more of the engine operating systems. For example, the controller may control or adjust a reference Figure 1 One or more of the engine operating systems 116 described herein. The action may be to stop or slow down the engine. In one example, the action may be to stop or reduce the fuel supply or fuel flow to the engine to stop or slow down the engine. In another example, the action may be to operate a valve that discharges the compressor exhaust pressure to the outside of the machine, thereby not providing air flow to the turbine (or providing a reduced air flow to the turbine). In yet another example, the action may be to adjust or close the variable turbine inlet vanes to adjust or cut off the air flow to the turbine. The action may also be to change the pitch of the fan blades. In one example, the command may be configured to slow down or shut down the engine when a triggering event is detected. In another example, the command may be configured to adjust the operation of one or more systems of an aircraft powered by an engine. For example, the command may be configured to stop the fuel supply to the engine, operate a valve that discharges the compressor exhaust pressure, or operate a variable turbine inlet vane to control the air flow to the turbine of the engine.

[0045] Reference now Figure 3-10 , describes various methods for detecting a trigger event based on a first speed of a first element and a second speed of a second element. Figure 3-10 The methods described can be performed using a controller. In one example, these methods are performed using reference Figure 1 The controller 114 described above is executed by the engine operating system 116, however, it is contemplated that other suitable control devices may be used. Upon detecting a triggering event, the controller 114 may trigger one or more of an alarm, a warning, an adjustment to one or more engine operating systems 116, or any other automatic system action.

[0046] As described above, the first speed of the first element and the second speed of the second element are connected by a gearbox (such as a reference Figure 1The gearbox 104 described herein may be associated with an engine. For example, the gearbox may include gears having a specific reduction ratio that reduces a first speed of a first element (e.g., a high speed input to the gearbox) to a second speed of a second element (e.g., a desired low speed output). The methods described herein may utilize the known relationship between the first speed and the second speed to detect an abnormal operating state of the engine, such as an overspeed condition.

[0047] First go to Figure 3 , an exemplary method for detecting a trigger event based on a first speed of a first element and a second speed of a second element is provided.

[0048] At block 302, a controller determines a relationship between a first speed of a first element and a second speed of a second element. In one example, the controller 114 may determine the relationship between the first speed and the second speed. The controller 114 may receive the first speed from the first speed sensor 110. The controller 114 may receive the second speed from the second speed sensor 112.

[0049] In one example, the relationship between the first speed and the second speed can be a ratio of the first speed to the second speed. In another example, the relationship is a difference between the first speed and the second speed. However, it is contemplated that the method can use any relationship or value that relates the first speed to the second speed.

[0050] At box 304, the controller detects a trigger event when the relationship between the first speed of the first element and the second speed of the second element exceeds a threshold. In one example, the controller 114 may detect a trigger event when the relationship between the first speed and the second speed exceeds a threshold. The threshold may be based on a known relationship between the first speed of the first element and the second speed of the second element. The known relationship may be set, for example, by a gearbox coupling the first element to the second element or a reduction ratio defined by a gear in a gearbox. In some non-limiting examples, for example, for a ducted engine, the gearbox ratio may be between about 2.0 and about 5.0. In another non-limiting example, for example, for an open rotor engine, the gearbox ratio may be between about 5 and about 15. In one example, the threshold of the relationship between the first speed of the first element and the second speed of the second element may be between about 1% and about 10% of the rated speed, between about 1% and about 5% of the rated speed, or in some examples, between about 1% and about 2% of the rated speed.

[0051] It should be understood that "exceeding" used herein may include any value exceeding a threshold value, and may include being higher or lower than a threshold value. In addition, the threshold value may be one or more values, and may include, for example, one or more of an upper limit and a lower limit defining a normal operating range of one or more of the first speed and the second speed.

[0052] Figure 4 4 is a graph 400 showing a first velocity 402 of a first element and a second velocity 404 of a second element over time. The first velocity 402 and the second velocity 404 have a relationship 410. The graph 400 includes a first region 406 and a second region 408.

[0053] The first region 406 shows the relationship 410 during normal operation. In the first region 406, the relationship 410 falls within a known or expected range. One or more thresholds may define the known or expected range of the relationship 410 during normal operation. For example, in the first region 406, the relationship 410 may be within a threshold and / or acceptable range, as determined by an exceeded limit of the relationship 410.

[0054] Second region 408 shows triggering events where there are differences in relationship 410. For example, a triggering event may indicate an engine overspeed condition. A triggering event may be at any point in second region 408 where relationship 410 falls outside of an expected range. In second region 408, relationship 410 exceeds one or more thresholds. That is, relationship 410 exceeds a known or expected range, or otherwise falls outside of a known or expected range. For example, in second region 408, relationship 410 may exceed a threshold, such as an overrun limit of relationship 410.

[0055] Upon determining that relationship 410 exceeds a threshold, the controller detects a triggering event and may take any suitable action, such as by transmitting an alarm, warning, or one or more commands to an engine operating system. For example, the command may bring relationship 410 within a threshold or below a threshold. In another example, the command may stop the engine.

[0056] Figure 5 5 is another graph 500 showing a relationship 510 between a first speed of a first element and a second speed of a second element over time. Graph 500 shows an upper limit 514 and a lower limit 516 of the relationship 510. One or more of the upper limit 514 and the lower limit 516 may be defined based on one or more of a margin, a buffer, or an error tolerance that establishes an acceptable range for the relationship 510 during normal engine operation or otherwise defines a normal range for the relationship 510. Graph 500 includes a first region 506 and a second region 508.

[0057] The first region 506 shows the relationship 510 during normal operation. In the first region 506, the relationship 510 falls within the upper limit of the exceedance 514 and the lower limit of the exceedance 516, which indicates that the relationship 510 is within a known or expected range.

[0058] The second region 508 shows triggering events where there are differences in the relationship 510. For example, the triggering event may indicate an engine overspeed condition. The triggering event may be at any point in the second region 508 where the relationship 510 falls outside of the expected range. In the second region 508, the relationship 510 exceeds the upper limit 514. That is, in the second region 508, the known or expected range is exceeded or otherwise falls outside of the known or expected range.

[0059] Point 520 on graph 500 shows a point at which the controller can detect a triggering event. At point 520, relationship 510 begins to exceed upper limit 514. Therefore, when relationship 510 reaches point 520 or at any point thereafter, the controller can take action, such as transmitting a command to one or more engine operating systems in response to the triggering event. For example, the command can bring relationship 510 within a threshold or below a threshold (e.g., within or between upper limit 514 and lower limit 516). In another example, the command can stop the engine.

[0060] Now go to Figure 6 , another exemplary method for detecting a trigger event based on a first speed of a first element and a second speed of a second element is provided.

[0061] At block 602, a controller determines a relationship between a first speed of a first element and a second speed of a second element. In one example, the controller 114 may determine the relationship between the first speed and the second speed. The controller 114 may receive the first speed from the first speed sensor 110. The controller 114 may receive the second speed from the second speed sensor 112.

[0062] In one example, the relationship between the first speed and the second speed can be a ratio of the first speed to the second speed. In another example, the relationship is a difference between the first speed and the second speed. However, it is contemplated that the method can use any relationship or value that relates the first speed to the second speed.

[0063] At block 604, the controller determines a rate of change of a relationship between a first speed of the first element and a second speed of the second element. In one example, the controller 114 determines the rate of change of the relationship.

[0064] At block 606, the controller detects a triggering event when a rate of change of a relationship between a first speed of the first element and a second speed of the second element exceeds a threshold. In one example, the controller 114 may detect a triggering event when a relationship between the first speed and the second speed exceeds a threshold.

[0065] Now go to Figure 7, another exemplary method for detecting a trigger event based on a first speed of a first element and a second speed of a second element is provided.

[0066] At block 702, the controller determines a rate of change of a first speed of a first element. In one example, reference Figure 1 The controller 114 described may determine the rate of change of the first speed. The controller 114 may receive the first speed from the first speed sensor 110.

[0067] At block 704, the controller determines a rate of change of a second speed of the second element. Figure 1 The controller 114 may determine the rate of change of the second speed. The controller 114 may receive the second speed from the second speed sensor 112.

[0068] At block 706, the controller determines a relationship between the rate of change of the first speed and the rate of change of the second speed of the second element. In one example, the controller 114 may determine a relationship between the rate of change of the first speed and the rate of change of the second speed.

[0069] In one example, the relationship between the rate of change of the first speed and the rate of change of the second speed can be the ratio of the rate of change of the first speed to the rate of change of the second speed. In another example, the relationship is the difference between the rate of change of the first speed and the rate of change of the second speed. However, it is contemplated that the method can use any relationship or value that relates the first speed to the second speed.

[0070] At block 708, the controller detects a triggering event when the relationship between the rate of change of the first speed and the rate of change of the second speed exceeds a threshold. In one example, the controller 114 may detect a triggering event when the relationship between the rate of change of the first speed and the rate of change of the second speed exceeds a threshold. In one non-limiting example, the threshold for the difference between the rate of change of the first speed and the rate of change of the second speed may be between about 1% per second and about 10% per second, between about 3% per second and about 7% per second, or in some aspects, about 5% per second (where the percentage (%) is a percentage of the rated speed).

[0071] Figure 8 8 is a graph 800 showing a rate of change of a first velocity 802 of a first element (e.g., acceleration of the first element) and a rate of change of a second velocity 804 of a second element (e.g., acceleration of the second element) over time. The rate of change of the first velocity 802 and the rate of change of the second velocity 804 have a relationship 810. Graph 800 includes a first region 806 and a second region 808.

[0072] The first region 806 shows the relationship 810 during normal operation. In the first region 806, the relationship 810 falls within a known or expected range. One or more thresholds can define the known or expected range of the relationship 810 during normal operation. For example, in the first region 806, the relationship 810 can be within a threshold and / or expected range, for example, defined by one or more exceedance limits of the relationship 810.

[0073] The second region 808 shows the relationship 810 during the triggering event. In the second region 808, the relationship 810 exceeds one or more thresholds. That is, the relationship 810 exceeds a known or expected range or otherwise falls outside a known or expected range. For example, in the second region 808, the relationship 810 may exceed a threshold and / or fall outside an expected range, for example, as defined by one or more exceedance limits of the relationship 810.

[0074] Upon determining that relationship 810 exceeds a threshold, the controller detects a triggering event and may take any suitable action, such as by transmitting an alarm, a warning, or one or more commands to an engine operating system.

[0075] Fig. 9 9 is another graph 900 showing a relationship 910 between a rate of change of a first speed of a first element and a rate of change of a second speed of a second element over time. Graph 900 shows an upper limit 914 and a lower limit 916 of the relationship 910. One or more of the upper limit 914 and the lower limit 916 can be defined based on one or more of a margin, a buffer, or an error tolerance that establishes an acceptable range for the relationship 910 during normal engine operation or otherwise defines a normal range for the relationship 910. Graph 900 includes a first region 906 and a second region 908.

[0076] The first region 906 shows the relationship 910 during normal operation. In the first region 906, the relationship 910 falls within the exceedance upper limit 914 and the exceedance lower limit 916, which indicates that the relationship 910 is within a known or expected range.

[0077] The second region 908 shows the relationship 910 during the triggering event. In the second region 908, the relationship 910 exceeds the upper limit 914. That is, in the second region 908, the relationship exceeds or otherwise falls outside of a known or expected range.

[0078] Point 920 on graph 900 shows a point at which the controller may detect a triggering event. At point 920, relationship 910 begins to exceed upper override limit 914. Thus, when relationship 910 reaches point 920 or at any point thereafter, the controller may take action, such as transmitting a command to one or more engine operating systems in response to the triggering event.

[0079] It is contemplated that monitoring the rate of change of the first speed of the first element and the rate of change of the second speed of the second element can detect a triggering event more quickly than simply monitoring the speeds. For example, following an event such as an overspeed condition, one axis may accelerate faster than expected while another axis may decelerate faster than expected.

[0080] Now go to Fig.10 , another exemplary method for detecting a triggering event based on a first speed of a first element and a second speed of a second element is provided.

[0081] At block 1002, the controller determines a rate of change of a first speed of a first element. In one example, reference Figure 1 The controller 114 described may determine the rate of change of the first speed. The controller 114 may receive the first speed from the first speed sensor 110.

[0082] At block 1004, the controller determines a rate of change of a second speed of the second element. Figure 1 The controller 114 may determine the rate of change of the second speed. The controller 114 may receive the second speed from the second speed sensor 112.

[0083] At block 1006, the controller determines a relationship between a rate of change of a first speed of the first element and a rate of change of a second speed of the second element. In one example, the controller 114 may determine a relationship between a rate of change of the first speed and a rate of change of the second speed. The controller 114 may receive the first speed from the first speed sensor 110 and calculate the rate of change. The controller 114 may receive the second speed from the second speed sensor 112 and calculate the rate of change.

[0084] In one example, the relationship between the rate of change of the first speed and the rate of change of the second speed can be the ratio of the rate of change of the first speed to the rate of change of the second speed. In another example, the relationship is the difference between the rate of change of the first speed and the rate of change of the second speed. However, it is contemplated that the method can use any relationship or value that relates the rate of change of the first speed to the rate of change of the second speed.

[0085] At block 1008, the controller determines a rate of change of a relationship between a rate of change of a first speed of the first element and a rate of change of a second speed of the second element. In one example, the controller 114 determines the rate of change of the relationship.

[0086] At block 1010, the controller detects a triggering event when a rate of change of a relationship between a rate of change of a first speed of a first element and a rate of change of a second speed of a second element exceeds a threshold. In one example, the controller 114 may detect a triggering event when a rate of change of a first speed and a rate of change of a second speed exceed a threshold.

[0087] In some embodiments, in reference Figure 3-10 In the described method, there may be multiple triggering events that prompt the controller to take different actions. For example, a first threshold value may indicate a first triggering event, and a second threshold value may indicate a second triggering event. The first triggering event may be when the controller detects that the relationship between the first speed and the second speed is outside of normal operation but has not yet reached an overspeed condition in the engine. The first triggering event may be a warning that an overspeed condition may occur. Therefore, when the first triggering event is detected, the controller may send an alarm to warn that an overspeed may occur, or other actions (e.g., slowing the engine) may be taken to prevent the overspeed condition from occurring. The second triggering event may be a final limit indicating that an overspeed condition occurs or has occurred. Therefore, when the second triggering event is detected, the controller may take action to alleviate the overspeed condition (e.g., stopping the engine).

[0088] Furthermore, in some embodiments, it is contemplated that a controller (e.g., reference Figure 1 The controller 114 described in the foregoing description may also sense or otherwise monitor the first speed of the first element via a first speed sensor (e.g., the first speed sensor 110) to determine whether the first speed exceeds a threshold. Similarly, the controller (e.g., the controller 114 described in the foregoing description) may also sense or otherwise monitor the first speed of the first element via a first speed sensor (e.g., the first speed sensor 110) to determine whether the first speed exceeds a threshold. Figure 1 The controller 114 described above may also sense or otherwise monitor a second speed of the second element via a second speed sensor (e.g., the second speed sensor 112) to determine whether the second speed exceeds a threshold. In one example, the controller may determine whether one or more of the first speed and the second speed exceeds a threshold (e.g., a negative overrun limit or a positive overrun limit). In another example, the controller may determine a rate of change of the second speed and determine whether the rate of change of the second speed exceeds a threshold (e.g., a negative overrun limit or a positive overrun limit). In one approach, one of the first speed and the second speed may have a negative overrun limit, and the other of the first speed and the second speed may have a positive overrun limit.

[0089] Fig.11 An example of a speed sensor in an engine is depicted. Fig.11is a schematic cross-sectional view of turbine engine 1110 taken along a centerline axis of turbine engine 1110 according to an embodiment of the present disclosure. Fig.11 Turbine engine 1110 is shown defining an axial direction A (extending parallel to a longitudinal centerline 1112 for reference) and a radial direction R perpendicular to axial direction A. Generally, turbine engine 1110 includes a fan section 1114 and a core turbine engine 1116 disposed downstream of fan section 1114 .

[0090] The depicted core turbine engine 1116 generally includes a casing 1118 that is substantially tubular and defines an annular inlet 1120. Fig.11 As schematically shown in FIG. 1 , the housing 1118 encloses in a serial flow relationship: a compressor section 1121, which includes a supercharger or low pressure (LP) compressor 1122, followed downstream by a high pressure (HP) compressor 1124; a combustion section 1126; a turbine section, which includes a high pressure (HP) turbine 1128, followed downstream by a low pressure (LP) turbine 1130; and an injection exhaust nozzle section 1132. A high pressure (HP) shaft 1134 or spool drives the HP turbine 1128 to the HP compressor 1124 so that the HP turbine 1128 and the HP compressor rotate in unison. A low pressure (LP) shaft 1136 drives the LP turbine 1130 to the LP compressor 1122 so that the LP turbine 1130 and the LP compressor 1122 rotate in unison. The compressor section 1121, the combustion section 1126, the turbine section, and the injection exhaust nozzle section 1132 together define a core air flow path.

[0091] Fan section 1114 includes a fan 1138 (eg, a variable pitch fan) having a plurality of fan blades 1140 coupled to a disk 1142 in a spaced-apart manner. Fig.11 1142, fan blades 1140 extend outwardly from disk 1142 generally along a radial direction R. Each fan blade 1140 is rotatable relative to disk 1142 about a pitch axis P by virtue of fan blades 1140 being operably coupled to actuating members 1144, which are configured to collectively and in unison change the pitch of fan blades 1140. Fan blades 1140, disk 1142, and actuating members 1144 are rotatable together about longitudinal centerline 1112 via fan shaft 1145, which is powered by LP shaft 1136 across power gearbox 1146 (also referred to as gearbox assembly 1146). Gearbox assembly 1146 includes a plurality of gears for adjusting the rotational speed of fan shaft 1145, and therefore the rotational speed of fan 1138 relative to LP shaft 1136, to a more efficient rotational fan speed.

[0092] Still reference Fig.11In an exemplary embodiment of the present invention, disk 1142 is covered by a rotatable fan hub 1148, which is aerodynamically shaped to facilitate airflow through a plurality of fan blades 1140. In addition, fan section 1114 includes an annular fan case or nacelle 1150 circumferentially surrounding fan 1138 and / or at least a portion of core turbine engine 1116. Nacelle 1150 is supported relative to core turbine engine 1116 by a plurality of circumferentially spaced outlet guide vanes 1152. In addition, a downstream section 1154 of nacelle 1150 extends over an outer portion of core turbine engine 1116 to define a bypass airflow passage 1156 therebetween.

[0093] During operation of the turbine engine 1110, a certain amount of air 1158 enters the turbine engine 1110 through the nacelle 1150 and / or the inlet 1160 of the fan section 1114. When the certain amount of air 1158 passes through the fan blades 1140, a first portion of air 1162 is directed or directed into the bypass airflow passage 1156, and a second portion of air 1164 is directed or directed into the upstream section of the core air flow path, or more specifically, is directed or directed into the annular inlet 1120 of the LP compressor 1122. The ratio between the first portion of air 1162 and the second portion of air 1164 is generally referred to as the bypass ratio. The pressure of the second portion of air 1164 is then increased when it is directed through the HP compressor 1124 and enters the combustion section 1126, where the highly pressurized air is mixed with fuel and combusted to provide combustion gases 1166.

[0094] The combustion gases 1166 are directed into and expanded through the HP turbine 1128, wherein a portion of the thermal and / or kinetic energy from the combustion gases 1166 is extracted via sequential stages of HP turbine stator blades 1168 coupled to the housing 1118 and HP turbine rotor blades 1170 coupled to the HP shaft 1134, thereby rotating the HP shaft 1134, which supports the operation of the HP compressor 1124. The combustion gases 1166 are then directed into and expanded through the LP turbine 1130. Here, a second portion of the thermal and kinetic energy is extracted from the combustion gases 1166 via sequential stages of LP turbine stator blades 1172 coupled to the housing 1118 and LP turbine rotor blades 1174 coupled to the LP shaft 1136, thereby rotating the LP shaft 1136. This extraction of energy supports the operation of the LP compressor 1122 and the rotation of the fan 1138 via the gearbox assembly 1146.

[0095] The first speed sensor 1180 is disposed on a first side (or input side) of the gearbox assembly 1146. In one example, the first speed sensor 1180 can be mounted to the LP shaft 1136. In another example, the first speed sensor 1180 can be mounted at other locations, such as on the low pressure compressor casing with a probe extending proximate to the LP shaft 1136, on a bearing support structure of the LP shaft 1136, on the gearbox assembly 1146, on a structure adjacent to the LP shaft 1136, or on or near a component coupled to the LP shaft 1136.

[0096] The second speed sensor 1182 is disposed on a second side (or output side) of the gearbox assembly 1146. In one example, the second speed sensor 1182 can be mounted to the fan shaft 1145. In another example, the second speed sensor 1182 can be mounted to other locations, such as on the engine front frame, on a bearing support structure for the fan shaft 1145, on the gearbox assembly 1146, on a structure adjacent to the LP shaft 1136, or on or near a component coupled to the fan shaft 1145. In some approaches, other sensors can be deployed near the tip of the blade 1140 to measure blade passage.

[0097] The combustion gases 1166 are then directed through the jet exhaust nozzle section 1132 of the core turbine engine 1116 to provide propulsive thrust. At the same time, the pressure of the first portion of air 1162 is significantly increased (e.g., 50% to 150%) as it is directed through the bypass airflow passage 1156 before being discharged from the fan nozzle exhaust section 1176 of the turbine engine 1110, also providing propulsive thrust. The HP turbine 1128, the LP turbine 1130, and the jet exhaust nozzle section 1132 at least partially define a hot gas path 1178 for directing the combustion gases 1166 through the core turbine engine 1116.

[0098] Fig.11 The turbine engine 1110 depicted in is only an example. In other exemplary embodiments, the turbine engine 1110 may have any other suitable configuration. For example, in other exemplary embodiments, the fan 1138 may be configured in any other suitable manner (e.g., as a fixed pitch fan), and may also be supported using any other suitable fan frame configuration. In addition, it should be understood that in other exemplary embodiments, any other suitable number or configuration of compressors, turbines, shafts, or combinations thereof may be provided. In still other exemplary embodiments, aspects of the present disclosure may be incorporated into any other suitable gas turbine engine (e.g., a turbofan engine, a propfan engine, a turbojet engine, and / or a turboshaft engine).

[0099] Now go to Fig.12 , turbine engine 1110 is shown with an alternative speed sensor placement. In particular, a first speed sensor 1180 ′ is disposed on the rear portion of LP shaft 1136 .

[0100] Go to Fig.13 , turbine engine 1110 is shown with another alternative speed sensor placement. In particular, a first speed sensor 1180 ″ is disposed on the center body of the jet exhaust nozzle section 1132 of turbine engine 1110 . A second speed sensor 1182 ′ is disposed on fan hub 1148 .

[0101] It is conceivable that Figure 11-13 Any combination of the configurations of the first speed sensors (1180, 1180', 1180") and the second speed sensors (1182, 1182') shown in FIG. 1 may be employed in the systems and methods described herein.

[0102] The system and method described herein can be used to detect an overspeed condition in an engine. By monitoring the speed of a first element on the input side of a gearbox connected to the engine and the speed of a second element on the output side of the gearbox, it is not necessary to sense the actual overspeed condition. Instead, the relationship between the two speeds can be monitored to determine when the two speeds deviate from a tolerable threshold. In this way, an impending overspeed event can be detected and responded to before the actual overspeed condition occurs. Therefore, the method described herein can detect and respond to an overspeed condition faster than conventional methods. Instead of waiting for the actual overspeed condition to occur, this method monitors the relationship between the speeds of two elements (the input side and the output side of the gearbox). By detecting when these speeds deviate from a tolerable threshold, it can identify a potential overspeed condition before the potential overspeed condition occurs. Conventional technology can rely on direct sensing of the overspeed condition. The technology described herein utilizes the relationship between the speeds of different components to allow for earlier detection of anomalies. By identifying an impending overspeed event before the impending overspeed event fully develops, the system can respond faster, thereby potentially preventing damage or failure that may occur in conventional methods that react only after the overspeed condition is detected.

[0103] Further aspects of the disclosure are provided by the subject matter of the following clauses:

[0104] A gas turbine engine comprises: a gearbox coupled to a first element and a second element; a first speed sensor positioned at an input side of the gearbox, the first speed sensor operable to detect a first speed of the first element; a second speed sensor positioned at an output side of the gearbox, the second speed sensor operable to detect a second speed of the second element; and a control system comprising a processor and a memory coupled to the processor, the processor being configured to: receive data from the first speed sensor; receive data from the second speed sensor; detect a trigger event based on the data from the first speed sensor and the data from the second speed sensor; and transmit a command to an engine operating system upon detection of the trigger event.

[0105] A gas turbine engine according to any preceding clause, wherein the first element is an input shaft of the gearbox or a component coupled thereto, and wherein the second element is an output shaft of the gearbox or a component coupled thereto.

[0106] A gas turbine engine as described in any preceding clause, wherein the input shaft is a high speed shaft, and wherein the output shaft is a low speed shaft.

[0107] A gas turbine engine as described in any preceding clause, wherein the triggering event is at least one of: exceeding a threshold difference between the first speed and the second speed; or exceeding a threshold rate of change between the first speed and the second speed.

[0108] A gas turbine engine according to any preceding clause, wherein the command is configured to stop the gas turbine engine.

[0109] A gas turbine engine according to any preceding clause, wherein the command is configured to stop fuel supply to the gas turbine engine, operate a valve to bleed compressor discharge pressure, or operate variable turbine inlet vanes to control air flow to a turbine of the gas turbine engine.

[0110] A gas turbine engine as in any preceding clause, wherein one or more of the first speed sensor or the second speed sensor comprises a variable reluctance sensor, a surface acoustic wave (SAW) sensor, a blade beta angle sensor, or an electric machine.

[0111] A control system for a gas turbine engine, the control system comprising: a memory; and a processor, the processor being coupled to the memory, the processor being configured to: receive data from a first speed sensor, the first speed sensor being operable to detect a first speed of a first element coupled to a gearbox of the gas turbine engine, the first speed sensor being positioned on an input side of the gearbox; receive data from a second speed sensor, the second speed sensor being operable to detect a second speed of a second element coupled to the gearbox, the second speed sensor being positioned on an output side of the gearbox; detect a trigger event based on the data from the first speed sensor and the data from the second speed sensor; and transmit a command to an engine operating system upon detecting the trigger event.

[0112] A control system as claimed in any preceding clause, wherein the first element is an input shaft coupled to the gearbox or a component coupled thereto, and wherein the second element is an output shaft of the gearbox or a component coupled thereto.

[0113] A control system as described in any preceding clause, wherein the input shaft is a high speed shaft, and wherein the output shaft is a low speed shaft.

[0114] A control system as described in any preceding clause, wherein the triggering event is at least one of: exceeding a threshold difference between the first speed and the second speed; or exceeding a threshold rate of change between the first speed and the second speed.

[0115] A control system as described in any preceding clause, wherein the command is configured to stop the gas turbine engine.

[0116] A control system as described in any preceding clause, wherein the command is configured to stop the supply of fuel to the gas turbine engine.

[0117] A method includes: sensing a first speed of a first element from a first speed sensor positioned on an input side of a gearbox in an engine; receiving data regarding a second speed of a second element from a second speed sensor positioned on an output side of the gearbox; detecting a trigger event based on the first speed and the second speed; and transmitting a command to an engine operating system upon detecting the trigger event.

[0118] A method according to any preceding clause, wherein the first element is an input shaft of the gearbox or a component coupled thereto, and wherein the second element is an output shaft of the gearbox or a component coupled thereto.

[0119] A method as in any preceding clause, wherein the command is configured to stop the engine.

[0120] A method as in any preceding clause, further comprising: determining a relationship between the first speed and the second speed; and detecting the triggering event when the relationship exceeds a threshold.

[0121] The method according to any of the preceding clauses further includes: determining the rate of change of the first speed; determining the rate of change of the second speed; determining the relationship between the rate of change of the first speed and the rate of change of the second speed; and detecting the trigger event when the difference exceeds a threshold.

[0122] The method of any preceding clause, further comprising: determining a relationship between the first speed and the second speed; determining a rate of change of the relationship; and detecting the trigger event when the rate of change of the relationship exceeds a threshold.

[0123] The method according to any of the preceding clauses further includes: determining the rate of change of the first speed; determining the rate of change of the second speed; determining the relationship between the rate of change of the first speed and the rate of change of the second speed; determining the rate of change of the relationship; and detecting the trigger event when the rate of change of the relationship exceeds a threshold.

Claims

1. A gas turbine engine, characterized in that: include: a gear box coupled to the first element and the second element; a first speed sensor positioned on an input side of the gearbox, the first speed sensor being operable to detect a first speed of the first element; a second speed sensor positioned on an output side of the gearbox, the second speed sensor being operable to detect a second speed of the second element; as well as A control system comprising a processor and a memory coupled to the processor, wherein the processor is configured to: receiving data from said first speed sensor; receiving data from the second speed sensor; detecting a triggering event based on the data from the first speed sensor and the data from the second speed sensor; and When the triggering event is detected, a command is transmitted to the engine operating system.

2. The gas turbine engine according to claim 1, characterized in that in, The first element is an input shaft of the gearbox or a component coupled thereto, and wherein the second element is an output shaft of the gearbox or a component coupled thereto.

3. The gas turbine engine according to claim 2, characterized in that in, The input shaft is a high speed shaft, and wherein the output shaft is a low speed shaft.

4. The gas turbine engine according to claim 1, characterized in that in, The triggering event is at least one of the following: a threshold difference between the first speed and the second speed is exceeded; or A threshold rate of change between the first speed and the second speed is exceeded.

5. The gas turbine engine according to claim 1, characterized in that in, The command is configured to stop the gas turbine engine.

6. The gas turbine engine according to claim 1, characterized in that in, The command is configured to stop a fuel supply to the gas turbine engine, operate a valve that vents compressor discharge pressure, or operate variable turbine inlet vanes to control air flow to a turbine of the gas turbine engine.

7. The gas turbine engine according to claim 1, characterized in that in, One or more of the first speed sensor or the second speed sensor includes a variable reluctance sensor, a surface acoustic wave (SAW) sensor, a blade beta angle sensor, or a motor.

8. A control system for a gas turbine engine, characterized in that: The control system comprises: Memory; and A processor is coupled to the memory, the processor being configured to: receiving data from a first speed sensor operable to detect a first speed of a first element of a gearbox coupled to the gas turbine engine, the first speed sensor being positioned on an input side of the gearbox; receiving data from a second speed sensor operable to detect a second speed of a second element coupled to the gearbox, the second speed sensor being positioned on an output side of the gearbox; detecting a triggering event based on the data from the first speed sensor and the data from the second speed sensor; and When the triggering event is detected, a command is transmitted to the engine operating system.

9. The control system according to claim 8, characterized in that: in, The first element is an input shaft coupled to the gearbox or a component coupled thereto, and wherein the second element is an output shaft of the gearbox or a component coupled thereto.

10. The control system according to claim 9, characterized in that: in, The input shaft is a high speed shaft, and wherein the output shaft is a low speed shaft.

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